The present invention is related to valve mounting installations and particularly to a fastening arrangement for mounting a valve device or the like on one side of a mounting plate or platform where access to the other side is generally limited and/or not practical.
One exemplary application of such a mounting installation is in the railroad industry where empty/load type valves are employed to sense a railroad car load condition in order to adjust the car braking effect accordingly and thereby prevent the occasion of slid flat wheels. Empty/load valves may be mounted on the slope sheet of certain types of railroad cars, in order to directly measure the weight of the commodity being transported, as opposed to indirectly measuring the car load condition by detecting spring deflection when mounted between the car body and truck.
In sensing the car load condition by directly measuring the weight of the commodity, an empty/load type valve is typically mounted on the slope sheet in surrounding relationship with a relatively large opening in the slope sheet. A heavy duty membrane associated with the empty/load valve encloses the opening so as to be increasingly deflected as the car is filled with the commodity being transported, such deflection being translated into the appropriate load setting of the empty/load valve.
In mounting the empty/load valve on the slope sheet, a plurality of cap screws may be employed. This, however, entails a costly operation to machine correspondingly threaded openings in the slope sheet with which the cap screws may be threadedly engaged. Alternatively, through openings may be made in the slope sheet without threads via which bolts may be passed freely. This requires that the mounting bolts be utilized with nuts, preferably of the locking type, to secure the empty/load valve in place. While this approach saves the expense of machining screw threads, it requires the time of an additional worker to hold the bolt head or nut from the inside of the car to prevent it from turning, while another worker turns the head or nut from the opposite side. It will be appreciated that this also entails expense in terms of man hours, which is exacerbated where safety regulations require a third person as an observer to safeguard the worker inside the car.
Still another alternative is to weld a threaded bolt or stud to the slope sheet so that a nut can be threaded in place without the bolt or stud turning. However, this requires removal of a broken bolt or stud, which entails a difficult operation.